Re: [PATCH, RFC] fix attr fit checking for filesystems which have lost their attr2

[Timothy Shimmin <tes@sgi.com>]

Eric,

So probably need something like this for xfs_bmap_compute_maxlevels()...


--Tim

===========================================================================
Index: fs/xfs/xfs_bmap.c
===========================================================================

--- a/fs/xfs/xfs_bmap.c	2008-03-31 16:32:24.000000000 +1000
+++ b/fs/xfs/xfs_bmap.c	2008-03-31 16:21:11.439806073 +1000
@@ -4154,16 +4154,21 @@ xfs_bmap_compute_maxlevels(
  	 * number of leaf entries, is controlled by the type of di_nextents
  	 * (a signed 32-bit number, xfs_extnum_t), or by di_anextents
  	 * (a signed 16-bit number, xfs_aextnum_t).
+	 *
+	 * Note that we can no longer assume that if we are in ATTR1 that
+	 * the fork offset of all the inodes will be (m_attroffset >> 3)
+	 * because we could have mounted with ATTR2 and then mounted back
+	 * with ATTR1, keeping the di_forkoff's fixed but probably at
+	 * various positions. Therefore, for both ATTR1 and ATTR2
+	 * we have to assume the worst case scenario of a minimum size
+	 * available.
  	 */
  	if (whichfork == XFS_DATA_FORK) {
  		maxleafents = MAXEXTNUM;
-		sz = (mp->m_flags & XFS_MOUNT_ATTR2) ?
-			XFS_BMDR_SPACE_CALC(MINDBTPTRS) : mp->m_attroffset;
+		sz = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
  	} else {
  		maxleafents = MAXAEXTNUM;
-		sz = (mp->m_flags & XFS_MOUNT_ATTR2) ?
-			XFS_BMDR_SPACE_CALC(MINABTPTRS) :
-			mp->m_sb.sb_inodesize - mp->m_attroffset;
+		sz = XFS_BMDR_SPACE_CALC(MINABTPTRS);
  	}
  	maxrootrecs = (int)XFS_BTREE_BLOCK_MAXRECS(sz, xfs_bmdr, 0);
  	minleafrecs = mp->m_bmap_dmnr[0];